Sign holder



FIG. 1 is a front perspective view of a sign holder;

FIG. 2 is a back perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a back view thereof;

FIG. 5 is a right side view thereof, the left side being a mirror image; and,

FIG. 6 is a top view thereof, the bottom view being identical.

The broken lines shown in the drawings are included for purposes of illustrating portions of the sign holder and form no part of the claimed design. 

CLAIM The ornamental design for a sign holder, as shown and described. 